1. Field of the Invention
The invention relates to fittings for connecting columns and beams of a steel frame construction and a method of connecting columns and beams and more particularly suitable for connecting beams having an I-shaped section to columns having an H-shaped or cross-shaped section.
2. Description of the Prior Art
In a prior art method of steel frame assembly for construction, all the welding operations are carried out in a field welding. In the method, however, beams must be provided at their end with bevelings and formed with notches for welding which may increase working cost of the beams. Moreover, maintenance of good quality control is difficult in the field quality control.
In another method column is provided with brackets previously welded thereto in a factory. In a building site, the bracket is connected to one end of a beam with connecting plates by means of high strength bolts. This method can overcome the problem with respect to the field welding, but a great many connections between columns and beams is required which makes the assembly of the construction complicated.
In yet another method, a column and a beam are connected by means of T-shaped members and connecting members bolted thereto respectively. This method has a disadvantage in that there may be great many working processes required for building the construction but each the connection has only a lower joint efficiency.
The first and second prior methods are inconvenient in transportation of the frame members such as columns because they are previously provided with the projections welded thereto in a factory.
In all the three prior methods, various kinds of members are required to fix the web of the beam to the column and horizontal stiffeners are required. These connections of the prior art intend to transmit a bending moment acting upon the beam through flanges thereof to the column and a shearing force acting upon the beam through the web thereof to the column, so that a great number of connecting members are required as above described which make the working and assembly complicated.